Printing System
===============

See the :ref:`printing-tutorial` section in Tutorial for introduction into
printing.

This guide documents the printing system in SymPy and how it works
internally.

Printer Class
-------------

.. module:: sympy.printing.printer

The main class responsible for printing is ``Printer`` (see also its
`source code
<http://git.sympy.org/?p=sympy.git;a=blob;f=sympy/printing/printer.py>`_):

.. autoclass:: Printer
    :members: doprint, _print

PrettyPrinter Class
-------------------

.. module:: sympy.printing.pretty.pretty
.. module:: sympy.printing.pretty.pretty_symbology
.. module:: sympy.printing.pretty.pretty_stringpict

Pretty printing subsystem is implemented in ``sympy.printing.pretty.pretty`` by
the ``PrettyPrinter`` class deriving from ``Printer``.  It relies on modules
``sympy.printing.pretty.stringPict``, and
``sympy.printing.pretty.pretty_symbology`` for rendering nice-looking formulas.

The module ``stringPict`` provides a base class ``stringPict`` and a derived
class ``prettyForm`` that ease the creation and manipulation of formulas that
span across multiple lines.

The module ``pretty_symbology`` provides primitives to construct 2D shapes
(hline, vline, etc) together with a technique to use unicode automatically when
possible.

MathMLPrinter
-------------

.. module:: sympy.printing.mathml

This class is responsible for MathML printing. See ``sympy.printing.mathml``.

More info on mathml content: http://www.w3.org/TR/MathML2/chapter4.html

LatexPrinter
------------

.. module:: sympy.printing.latex

This class implements LaTeX printing. See ``sympy.printing.latex``.

See also the extended LatexPrinter: :ref:`Extended LaTeXModule for Sympy <extended-latex>`

Gtk
---

.. module:: sympy.printing.gtk

You can print to a grkmathview widget using the function print_gtk located in
sympy.printing.gtk (it requires to have installed gtkmatmatview and
libgtkmathview-bin in some systems).

GtkMathView accepts MathML, so this rendering depends on the mathml representation of the expression

Usage::

    from sympy import *
    print_gtk(x**2 + 2*exp(x**3))

PythonPrinter
-------------

.. module:: sympy.printing.python

This class implements Python printing. Usage::

    In [1]: print_python(5*x**3 + sin(x))
    x = Symbol('x')
    e = sin(x) + 5*x**3

Preview
-------

Useful function is ``preview``:

.. module:: sympy.printing.preview

.. autofunction:: preview

And convenience functions:

.. autofunction:: pngview
.. autofunction:: pdfview
.. autofunction:: dviview